What do you mean by fading in communication?
Fading occurs when there are significant variations in received signal amplitude and phase over time or space. Fading can be frequency-selective—that is, different frequency components of a single transmitted signal can undergo different amounts of fading.
What is fading and its causes?
What Causes Fading. Fading can be caused due to natural weather disturbances, such as rainfall, snow, fog, hail and extremely cold air over a warm earth. Fading can also be created by man made disturbances, such as irrigation, or from multiple transmission paths, irregular earth surfaces, and varying terrains.
What is fading and its types?
The Fading types are divided into large scale fading and small scale fading (multipath delay spread and doppler spread). Flat fading and frequency selecting fading are part of multipath fading where as fast fading and slow fading are part of doppler spread fading.
What causes fading in wireless communication?
In Wireless Communication, fading refers to the attenuation of the transmitted signal power due to various variables during wireless propagation. These variables can be atmospheric conditions such as rainfall and lightning, geographical position, time, radio frequency etc.
What is fading in wireless communication PPT?
Loss of strength, A periodic reduction in the received strength of a radio transmission. time variation of the received signal power caused by changes in the transmission medium or path.
What is fading and Doppler spread?
Time-varying fading due to scattering objects or transmitter/receiver motion results in Doppler spread. The time spreading effect of small-scale or microscopic fading is manifested in the time domain as multipath delay spread and in the frequency domain as channel coherence bandwidth.
How many types of fading are there?
Flat Fading: In flat fading, all frequency components get affected almost equally. Flat multipath fading causes the amplitude to fluctuate over a period of time. Selective Fading: Selective Fading or Selective Frequency Fading refers to multipath fading when the selected frequency component of the signal is affected.
What is difference between fading and attenuation?
Attenuation is the lowering of the signal not frequency depending but (normally) over all frequencies. Fading is the lowering of the signal in time and freqnency, phase can also be effected.
What are the effects of fading?
A transmitted signal undergoes changes while traveling through the propagation path to the receiver. The effect of these changes is commonly called fading. In free-space, a signal follows one path and arrives at the receiver with little attenuation.
What is fading channel in wireless communication?
A fading channel is a communication channel that experiences fading. In wireless systems, fading may either be due to multipath propagation, referred to as multipath-induced fading, weather (particularly rain), or shadowing from obstacles affecting the wave propagation, sometimes referred to as shadow fading .
What is fading in mobile technology?
In mobile scenario, fading depends on obstacles over the path which are varying with respect to time. These obstacles create complex transmission effects to the transmitted signal. The figure-1 depicts amplitude versus distance chart for slow fading and fast fading types which we will discuss later.
What is fast fading in signal processing?
When the signals arrive from all the directions in the plane, fast fading will be observed for all directions of motion. Fast fading occurs when channel impulse response changes very rapidly within the symbol duration.
How to deal with fading in computer networks?
Besides diversity, techniques such as application of cyclic prefix (e.g. in OFDM) and channel estimation and equalization can also be used to tackle fading. ^ Tse, David; Viswanath, Pramod (2006).